Chen Hao placed the glue gun at the starting point of window number eleven and pulled the trigger. The glue slowly squeezed out, pushing along the edge of the window frame. His movements were much steadyer than last night; his wrists were no longer trembling, and his breathing was even.

Carl stood beside him, handing him the scraper, his hands trembling slightly. "My hand feels like it's cramping," he said. "I only slept for a little over an hour last night."

"You're lucky you can still stand." Susan walked over from the materials cabinet, carrying two buckets of newly mixed sealant. "The layering problem is solved. The heating pad has been kept at a constant temperature for three hours, and now the texture is stable."

Nana stood in front of the terminal, the screen scrolling with data. "The current ambient temperature is 14 degrees Celsius, and the humidity is 62 percent, which is suitable for application and curing," she said. "The recommended application window is from 9 a.m. to 2 p.m.

"Then hurry up." Chen Hao wiped his face, his sleeves covered in dried glue stains. "There are still more than thirty panels to finish. Don't get stuck on the last few."

They kept working. One panel after another, they dismantled, cleaned, painted, installed, and tested. The pace wasn't as intense as the night before, but they didn't dare slack off. Everyone knew that if even one panel failed, all the previous efforts would have to be redone.

Before noon, the thirty-fifth window was installed. The detector lit up with a green light. Susan put a checkmark on the form, her pen almost piercing the paper.

"Fifteen doors passed in a row," she said. "Not a single one needed to be redone."

“That proves we didn’t just rely on luck,” Carl said, leaning against the wall, “we really have mastered the technique.”

Chen Hao didn't speak, but squatted down to examine the newly installed window. He reached out and touched the seams, then leaned closer to listen. The wind was blocked out, leaving only the hum of the machines in the workshop.

“It sounds like a safe house,” he said.

At 1 PM, the 40th window passed the test. Nana updated the progress bar: seven windows remaining.

Just then, Carl was tightening the last screw when his hand slipped, and the wrench hit his foot. He cried out and sat down on the ground, not getting up for a long time.

"Take a break," Susan said, glancing at the time. "You should take a break too."

“I’m fine,” Carl waved his hand. “My toe just went numb for a bit.”

“If you keep pushing yourself, you’ll apply the glue crookedly and we’ll have to take it all down,” Chen Hao said. “Go lie down for ten minutes, then come back and continue.”

Carl slowly got up and limped towards the rest area. Susan followed him to get him an ice pack.

Only Chen Hao and Nana remained in the workshop. The testing instrument was pressurizing the forty-first window. The reading rose steadily and then stopped at the standard value.

"Pass," Nana said.

Chen Hao breathed a sigh of relief and sat down on the toolbox. "At least I don't have to live in fear anymore."

"According to the system records, since 2 a.m., the sealing and reinstallation of 27 doors and windows has been completed." Nana looked at the screen. "A total of 186 kilograms of type A silicone gel and 62 kilograms of agent B have been used, with the error controlled within three per thousand."

"Do you still remember these numbers?"

“All operational data has been archived,” she said. “This includes the installation time of each window, inspection results, and the worker's identification number.”

Chen Hao grinned: "If anyone dares to say we're messing around, just throw this report in their face."

Susan returned just then, holding a thermometer. "Those two buckets of glue were placed too close to the side, and there's a slight sediment at the bottom after it cooled down overnight," she said. "Even though they were heat-treated, I'm still worried that the other doors will be affected."

“Then let’s test each bucket individually.” Chen Hao stood up. “Take a sample before using each bucket, do a string test, and only put it on the wall if there are no problems.”

“There’s another problem.” Susan frowned. “The east wall is slightly deformed. When the forty-third panel was pressed together, the gap in the upper right corner was noticeably larger than in other areas.”

Chen Hao went over to take a look. The window frame had been installed, but the four corners were not under equal pressure, with one corner hanging about two millimeters off the ground.

"It's like the wall is tilted by itself?" He pushed the wall with his hand, but the cement surface didn't budge.

Nana pulled up the building structure diagram and projected it on the wall. "The site has been built for seven years, and there has been slight settlement in the foundation," she said. "The largest settlement in the east section is 3.2 centimeters, which has caused the window openings to be slightly distorted."

"So glue alone can't fill it?" Chen Hao asked.

“Yes,” Nana nodded, “structural compensation is needed.”

How to fix it?

"I suggest installing adjustable metal shims at the four corners of the window frame," she said, showing the 3D model. "During installation, the thickness can be manually adjusted according to the size of the gaps to achieve uniform pressing."

Do they even have this thing?

“We have some discarded shock-absorbing pad components in our inventory, and the material meets the requirements.” Nana pulled up the supplies list. “There are forty-seven sets in total, which is just enough.”

"I'll go find it." Chen Hao stood up. "While Karl is still resting, let's quickly revise the plan."

He found the parts box and pulled out a pile of rusty metal sheets. After cleaning and polishing them, he sorted them by size. Susan took a ruler, measured each sheet, and labeled them with the appropriate window number.

Carl returned half an hour later, still limping slightly. He paused, surprised to see them installing gaskets. "What's going on?"

"Make the window seal even tighter." Chen Hao stuffed a piece into the corner of the window. "Look, it's sealed perfectly now."

Karl reached out and touched it, nodding: "It's stronger than before."

The construction speed slowed down afterward, but the quality became more consistent. Each window underwent three inspections: an initial test after installation, a pressure test, and a final test after two hours of settling.

At 5:18 PM, the forty-seventh window—the last one on the north side—was installed.

Nana initiated the detection program. The pressure gradually increased, and the sensor readings stabilized. Ten seconds, twenty seconds, half a minute passed, but the alarm did not sound.

“Pass,” she said.

No one cheered. The four people stood around the instrument, staring at the green "pASS" on the screen for a full minute.

“Passed everything,” Susan said softly.

"All forty-seven panels meet the standards," Nana confirmed. "Not a single one required rework, and not a single one leaked."

Carl plopped down on the floor, leaning against the wall. "I've never worked this hard in my life," he said. "I wasn't even this punctual for my mother's wedding."

“You were only five years old when your mother got married,” Chen Hao said.

“That doesn’t affect my art of conversation.” Carl closed his eyes. “Right now, I just want to sleep.”

"Don't sleep yet." Susan opened her laptop. "We were halfway through the test when the wind speed outside the north window suddenly spiked to twelve meters per second, creating a momentary negative pressure difference. The instrument alarmed once, but then it went back to normal."

"Is it external interference?" Chen Hao asked.

"Yes." Nana pulled up the weather data. "The strong gusts lasted for forty-seven seconds, which is considered an extreme condition."

"Shall we try something even tougher?" Chen Hao asked her. "Let's increase the pressure by 1.5 times and see if we can handle it."

“Destructive testing carries a high risk,” Nana said. “If it fails, the entire project will have to be redone.”

"We've already passed anyway," Chen Hao laughed. "Why not take a gamble?"

None of the three objected.

Nana adjusted the parameters. The detector was repressurized, and the target value jumped to 1.5 times the standard.

Time ticked by. Ten minutes passed, and the pressure remained stable. The sensor showed no abnormal fluctuations.

"Passed," Nana announced.

“Wind pressure resistance has increased by forty percent.” Susan looked at the summary table. “Rainwater infiltration threshold has doubled. This performance is even higher than the design standard.”

"So, even if there's a typhoon outside, the house won't leak?" Karl opened his eyes.

"The premise is that the roof doesn't collapse," Chen Hao said.

"The roof structure is 91% intact," Nana added.

"That seems pretty reliable." Karl closed his eyes again.

Chen Hao walked to the last window and placed his hand on the seam. The wind blew outside, but inside it was as quiet as ever.

“This time, the wind can’t blow it through,” he said.

Nana began uploading files. The "Extreme Environment Door and Window Sealing Construction Manual V1.0" was generated and automatically archived in the base's knowledge base. Key steps were set as mandatory processes, with mixing ratios, stirring times, and curing cycles all locked. Incorrect operation would trigger a voice warning and interrupt material supply.

"From now on, anyone who tries to slack off won't be allowed by the system." Chen Hao looked at the screen. "They won't even be able to get the glue out."

“It has been linked to future building module design suggestions,” Nana said. “This process will be automatically recommended for new projects.”

Susan put the last bucket of sealant into the special cabinet and labeled it: "Certified material, batch 2024-07-19".

She closed the cabinet door and locked it.

Carl was still leaning against the wall, clutching the scraper in his hand. His eyelids were drooping, but he refused to leave.

"Let go," Chen Hao said. "The tools can still be used tomorrow."

“I’m not afraid of losing it,” Carl muttered. “I’m afraid that if I let go, this whole thing will really be over.”

Chen Hao smiled but didn't reply.

He opened the test summary sheet and read through it page by page. Each section had a number, date, responsible person, and result. The densely packed data, like a net, completely plugged any loopholes.

“We were always thinking about speed,” he said. “But the faster we went, the more mistakes we made. Now that we’ve slowed down, we’ve actually succeeded.”

“Because this time it’s not just about fixing windows,” Susan said, “it’s about turning how to fix them into a set of rules.”

Nana has completed the archiving. A notification pops up on the screen: [Process upgrade complete, system synchronization successful].

She closed the terminal, and the blue light went out.

Only a few overhead lights remained on in the workshop. Tools were scattered all over the floor, empty buckets were piled in a corner, and the testing equipment stood quietly in standby mode.

Chen Hao placed the summary sheet on the workbench and sat down. He felt tired, but at peace.

Carl yawned, and the scraper in his hand finally slipped and hit the concrete floor with a dull thud.